Plated pillar package formation

Abstract

A method involves plating pillars of electrically conductive material up from a seed layer located on a substrate, surrounding the pillars with a fill material so that the pillars and fill material collectively define a first package, and removing the substrate from the first package.

1. A method of forming a package, the method comprising:
 providing a first sacrificial layer on a substrate, wherein the substrate includes a first seed layer provided thereon; 
 forming openings in the first sacrificial layer to expose portions of the first seed layer; 
 plating the exposed portions of the first seed layer with a conductive metal to form pillars; 
 removing the first sacrificial layer; 
 providing a first fill material on the substrate adjacent the pillars, wherein an outer surface of the first fill material is planar to an upper surface of the pillars; and 
 removing the substrate. 
 
     
     
       2. The method of  claim 1 , further comprising forming the first seed layer on the substrate before the first sacrificial layer is formed. 
     
     
       3. The method of  claim 2 , wherein said forming the first seed layer comprises forming contacts and traces. 
     
     
       4. The method of  claim 3 , wherein said forming contacts and traces comprises metalizing the contacts and the traces. 
     
     
       5. The method of  claim 4 , wherein the first sacrificial layer is a photoresist. 
     
     
       6. The method of  claim 5 , wherein the first fill material is an insulator. 
     
     
       7. The method of  claim 1 , wherein said plating comprises electroplating or electroless-plating. 
     
     
       8. The method of  claim 1 , wherein at least some of the openings have a width of 50 μm or less. 
     
     
       9. The method of  claim 8 , wherein at least some of the openings have a pitch of 50 μm or less. 
     
     
       10. The method of  claim 1 , wherein at least some of the openings have a width of 20 μm or less. 
     
     
       11. The method of  claim 10 , wherein at least some of the openings have a pitch of 20 μm or less. 
     
     
       12. The method of  claim 1 , wherein a first set of the openings have a first width and a second set of the openings have a second width that differs from the first width. 
     
     
       13. The method of  claim 1 , further comprising:
 providing a second seed layer over the pillars and the first fill material; 
 providing a second sacrificial layer over the second seed layer, the pillars, and the first fill material; 
 forming openings in the second sacrificial layer; 
 forming pillars in the openings of the second sacrificial layer; 
 removing the second sacrificial layer; and 
 providing a second fill material over the second seed layer and the first fill material. 
 
     
     
       14. The method of  claim 1 , wherein the first fill material comprises a curable or self-hardening material. 
     
     
       15. A method of forming a package, the method comprising:
 metalizing at least a portion of a surface of a substrate to form a seed layer; 
 providing a photoresist over the seed layer and the substrate; 
 forming openings in the photoresist to expose portions of the seed layer; 
 plating the exposed portions of the seed layer with a conductive metal to form interconnects; 
 after said plating, removing the photoresist; 
 providing a fill material on the substrate adjacent the interconnects after removing the photoresist, wherein an outer surface of the fill material forms a substantially planar surface with an outer surface of the interconnects; and 
 removing the substrate. 
 
     
     
       16. The method of  claim 15 , wherein said metalizing comprises a vapor deposition process. 
     
     
       17. The method of  claim 15 , wherein said metalizing comprises forming contacts and traces. 
     
     
       18. The method of  claim 17 , wherein said forming contacts and traces comprises metalizing the contacts and the traces. 
     
     
       19. The method of  claim 15 , wherein the fill material is an insulator. 
     
     
       20. The method of  claim 15 , wherein said plating comprises electroplating or electroless-plating. 
     
     
       21. The method of  claim 15 , wherein at least some of the openings have a width of 50 μm or less and a pitch of 50 μm or less. 
     
     
       22. The method of  claim 15 , wherein at least some of the openings have a width of 20 μm or less and a pitch of 20 μm or less. 
     
     
       23. The method of  claim 15 , wherein a first set of the openings have a first width and a second set of the openings have a second width that differs from the first width. 
     
     
       24. The method of  claim 15 , wherein the fill material comprises a curable or self-hardening material.